Agents that produce analgesia are called Analgesic. Analgesia – state of relative insensitivity to pain. Capacity to tolerate pain is increased without loss of consciousness

1. NARCOTIC AND NON
NARCOTIC ANALGESIC

2. • Agents that produce analgesia
• Analgesia – state of relative insensitivity to
pain.
• Capacity to tolerate pain is increased without
loss of consciousness

3. Classification
• Opioid Analgesic
• Non opioid analgesic

12. CODEINE
• One tenth analgesic as morphine
• Free phenolic grp. Is important for greater
potency.
H3CO
N
CH3
O
OH

13. MEPERIDINE HCl
• Discovered in 1930
• Analgesic propeties observed during pharmacological work up.
• Replacement of C4 phenyl group of meperidine by H, alkyl, aryl and
heterocyclic group decreases analgesic activity.
• Introduction of m-OH on phenyl ring increases the activity.
• Presence of phenyl and ester group at 4th position of 1-methyl piperidine
results in optimal activity.
• Replacement of carberhoxy group in meperidine by acyloxy group gives
better activity.
N
COOC 2H5
CH3

14. Anileridine
• Replacement of 4-phenyl group by hydrogen, aroalkyl or
heterocyclic grp. Results in reduced activity.
• Replacement of COOC2H5 BY OCOC2H5 gives better activity.
• 4 times more active than meperidine.
N
COOC2H5
N
H2

15. DIPHENOXYLATE
• It is weak opioid agonist
• Available combined with atropine.
• Diphenylmethane and CN moeity is imp.
• Ester metabolised to carboxylic acid which is active opioid
agent.
N
COOC 2H5
H5C6
H5C6
CN

16. LOPERAMIDE HCl
N
OH
Cl
(H5C6)2
O
N
C
H3
CH3
Acts on mu receptor in the myenteric plexus of the large
intestine.
Effective for the treatment of Diarrhea.

17. FENTANYL CITRATE
• Phenyl ring and acyl group are seperated from
the ring by nitrogen.
N
O
C2H5
N
CH2CH2C6H5

18. METHADONE HCl
• Simplification of morphine nucleus by opening
of nitrogen ring results in methadone series of
compounds.
COC2H5
H5C6
N
C
H3
CH3
CH3

19. • Insertion of m-hydroxyl group in one of the
phenyl ring of methadone causes decrease in
analgesic activity.
• Methadone series compounds are more
potent analgesic.
• Replacement of COC2H5 by H will decrease
the activity.
• Removal of any 2 phenyl grp. Decreases the
activity

20. PROPOXYPHEN HCl
COOC2H5
H5C6H2C
N
C
H3
CH3
CH3

21. MORPHINANS
• LEVORPHENOL TARTARATE
• Morphinans are made by removing E ring of morphine, the
4,5- ether bridge.
• LEVORPHENOL TARTARATE is 7.5 times more potent than
morphine.
• Loss of 4,5 epoxide and 7,8 double bond allows greater
flexibility and leads to increased binding affinity at all opioid
receptor subtypes compared with morphine.
O
H
N
CH3

22. BENZOMORPHANS
• Structural modification of morphine ring by removing
C ring of morphinan structure gives benzomorphans.
• Eg. PENTAZOCINE
• It is mixed agonist/antagonist displaying differing
intrinsic activity at opioid receptors.
• At μ receptor-partial agonist and weak antagonist
O
H
N
C
H3
CH3
CH3
CH3

23. NARCOTIC ANTAGONIST
• Blocks effects of narcotics
• Used in the treatment of overdose of narcotic.
• Structurally related to morphine
• Except group attached to nitrogen
• They prevent excessive respiratory depression
caused by administration of morphine

24. NALORPHINE HCl
• Mixed opioid agonist-antagonist
• Mu-antagonist, Kappa-agonist
• Uses- treat narcotic induced respiratory
depression, treat overdose of morphine,
methadone, levorphanol
O
H
N
O
OH
CH2
.HCl

25. LEVALLORPHAN TARTARATE
• Antagonises opioid effect by competing for
the same receptor site.
• Binds to mu receptor.
• Uses- complete or partial reversal of narcotic
depression, respiratory depression due to
opioids.
O
H
N
O
CH2
O
H
OH
O
O
OH
O
H
.

26. NALOXONE HCl
• Antagonizes opioid effects by competing for same
receptor sites (mu)
• Uses- complete or partial reversal of narcotic
depression, including respiratory depression induced
by narcotics, propoxyphen, methadone. Used in
treatment of narcotic overdose.
O
H
N
O
CH2
O
.HCl